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Retinal Scanning . Biometrics Presentation by Ajinkya Bhave 30 th April, 2003. Structure of the Eye. What is the Retina?. A very thin layer of tissue on the back of the eye (1/50 “ thick) Has rods and cones to sense light and colour Transmits impulses through the optic nerve
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Retinal Scanning Biometrics Presentation by Ajinkya Bhave 30th April, 2003
What is the Retina? • A very thin layer of tissue on the back of the eye (1/50 “ thick) • Has rods and cones to sense light and colour • Transmits impulses through the optic nerve • Multiple layers of cells comprise the retina • Retina = CCD + DSP all in one
Background • One of the earliest biometric techniques – early 1930’s • Very high level of accuracy (0.0001% FAR) • One of the most ‘information-rich’ biometrics (over 400 feature points) • Considered an ‘intrusive’ technology
Principle • Identifies individuals by retinal blood vessel pattern • Unique for each individual (including twins) • Patterns do not change over an individual’s lifetime • Exceptions include diabetes and macular degenerative diseases
Technique • Subject looks into a focussing camera at close range (~ ½ inch) for several seconds • Low power IR (~7mW) is directed into the pupil • Resulting picture is captured by the camera • May require several such images to get a good template • Image processing filters out relevant feature points • Pattern is matched against stored templates
Commercial Systems • Only 2 currently in the market • Widely differing hardware • Widely differing price tags
System specifications • Enrollment time : less than 1 minute ; • Stand alone verification time : 1.5 seconds ; • Stand alone recognition time. : less than 5 seconds with 1500 persons enrolled ; • Storage capacity : 3000 individuals in flash RAM memory • Template size : 96 bytes • Cost : $2000-$2500
System specifications • Handheld device • Variable capture distances – ? upto 3 feet? • Uses aspheric lens array to get this range • Laser opthalmoscope captures retinal image • Template size : 50 bytes • Estimated cost: ~ $200
Strengths • Accuracy – FAR rates as low as 0.0001% • Stability of biometric sample • Resistant to fraud • Small template size – large database on a small, standalone device
Weaknesses • Cumbersome to use practically • Trained operative needed during operation • Consumer perceptions (safety) • Cost (apparently not anymore with RT)
Applications • Security in Military areas • Access-control … • Screening … • Tracking livestock across regions – (disease-spread prevention)